Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Received-SPF: Pass (protection.outlook.com: domain of nvidia.com designates
 216.228.117.160 as permitted sender) receiver=protection.outlook.com;
 client-ip=216.228.117.160; helo=mail.nvidia.com; pr=C
Date:   Tue, 6 Jun 2023 12:43:44 -0700
From:   Nicolin Chen <nicolinc@nvidia.com>
To:     Jason Gunthorpe <jgg@nvidia.com>
CC:     "Tian, Kevin" <kevin.tian@intel.com>,
        "Liu, Yi L" <yi.l.liu@intel.com>,
        "joro@8bytes.org" <joro@8bytes.org>,
        "alex.williamson@redhat.com" <alex.williamson@redhat.com>,
        "robin.murphy@arm.com" <robin.murphy@arm.com>,
        "baolu.lu@linux.intel.com" <baolu.lu@linux.intel.com>,
        "cohuck@redhat.com" <cohuck@redhat.com>,
        "eric.auger@redhat.com" <eric.auger@redhat.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "mjrosato@linux.ibm.com" <mjrosato@linux.ibm.com>,
        "chao.p.peng@linux.intel.com" <chao.p.peng@linux.intel.com>,
        "yi.y.sun@linux.intel.com" <yi.y.sun@linux.intel.com>,
        "peterx@redhat.com" <peterx@redhat.com>,
        "jasowang@redhat.com" <jasowang@redhat.com>,
        "shameerali.kolothum.thodi@huawei.com" 
        <shameerali.kolothum.thodi@huawei.com>,
        "lulu@redhat.com" <lulu@redhat.com>,
        "suravee.suthikulpanit@amd.com" <suravee.suthikulpanit@amd.com>,
        "iommu@lists.linux.dev" <iommu@lists.linux.dev>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-kselftest@vger.kernel.org" <linux-kselftest@vger.kernel.org>,
        "Duan, Zhenzhong" <zhenzhong.duan@intel.com>
Subject: Re: [PATCH v2 01/11] iommu: Add new iommu op to create domains owned
 by userspace
Message-ID: <ZH+McCPS14Wc25JL@Asurada-Nvidia>
References: <20230511143844.22693-1-yi.l.liu@intel.com>
 <20230511143844.22693-2-yi.l.liu@intel.com>
 <BL1PR11MB5271B553140BB729AF4389AB8C7C9@BL1PR11MB5271.namprd11.prod.outlook.com>
 <ZGfDrRDI50oGih2r@Asurada-Nvidia>
 <BN9PR11MB52766A760580E6FBB995A33F8C419@BN9PR11MB5276.namprd11.prod.outlook.com>
 <ZG2fVj41GgosR1dk@Asurada-Nvidia>
 <BN9PR11MB5276F1410A11ED631CE6824F8C419@BN9PR11MB5276.namprd11.prod.outlook.com>
 <ZG681VohNlw2vvLD@Asurada-Nvidia>
 <ZH897AGywGVbt51Z@nvidia.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <ZH897AGywGVbt51Z@nvidia.com>
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jun 2023 19:44:03.2646
 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: de3576b0-930e-4642-5b42-08db66c661d6
X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a
X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com]
X-MS-Exchange-CrossTenant-AuthSource: DM6NAM11FT011.eop-nam11.prod.protection.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Anonymous
X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem
X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB7874
X-Spam-Status: No, score=-1.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,
        DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FORGED_SPF_HELO,
        RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_NONE,
        T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=no autolearn_force=no
        version=3.4.6
X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on
        lindbergh.monkeyblade.net
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Jun 06, 2023 at 11:08:44AM -0300, Jason Gunthorpe wrote:
> On Wed, May 24, 2023 at 06:41:41PM -0700, Nicolin Chen wrote:
> 
> > Upon a quick check, I think we could. Though it'd be slightly
> > mismatched with the domain_alloc op, it should be fine since
> > iommufd is likely to be the only caller.
> 
> Ideally the main op would return ERR_PTR too

Yea. It just seems to be a bit painful to change it for that.

Worth a big series?

Thanks
Nic